Utilization of oxidized polyolefin waxes for textile finishing

ABSTRACT

The invention relates to the utilization of oxidized polyolefin that are produced with the aid of metallocene catalysts for textile finishing.

The present invention relates to the use of oxidized polyolefinic waxes.

The final finishing of textile yarns, wovens and knits in cellulosicfibers, wool, synthetic fibers and blends thereof with softeners basedon soft or hard polyethylene waxes is established practice in today'stextile industry. Aqueous dispersions of oxidized polyethylenic waxesare used in particular.

As well as providing a softening, hand-improving effect, textilesofteners have to perform other functions. The melamine resinsfrequently used in textile finishing to provide crease resist and easycare properties have an appreciably adverse effect on hand, sewing andsoil release performance. This adverse effect is substantiallycompensated by modern softeners based on polar polyethylenic waxes. Toreduce costs and labor at final textile finishing, the polyethylene waxdispersions have to be compatible with the melamine derivatives in orderthat they may be applied from one aftertreating bath. It is here thatthe hard, high molecular weight polar polyethylenic waxes having anumber average molecular weight (Mn) above 2000 g/mol have distinctlybetter properties as an active substance than low molecular weight, softpolar polyethylenic waxes.

The disadvantage with hard polyethylene wax oxidates of high molecularweight is the high cost and inconvenience needed to emulsify them. Theemulsification has to be carried out in a sealed autoclave attemperatures of 135-155° C. This not only takes more time but alsorequires higher energy costs and also a high consumption of coolingwater to cool the ready-produced dispersion down to room temperature.

It has now been found that oxidized waxes based on polyethylene waxesproduced using metallocene catalysts are very useful as textilesofteners and combine this usefulness with the advantage of readyemulsifiability at low temperatures.

The invention accordingly provides for the use for textile finishing ofoxidized polyolefinic waxes produced using metallocene catalysts.

The polyolefinic waxes used are preferably ethylene homo- or copolymerwaxes including 0-30% by weight of an olefin comonomer having a chainlength of 3-18 carbon atoms.

The olefin comonomers used are preferably propene, 1-butene, 1-hexene,1-octene, 1-octadecene or styrene.

The oxidized polyolefinic waxes preferably have a drop point of 85 to127° C.

The oxidized polyolefinic waxes more preferably have a drop point of 90to 120° C.

The oxidized polyolefinic waxes preferably have a melt viscosity (at140° C.) of 10 to 10000 mPa·s.

The oxidized polyolefinic waxes more preferably have a melt viscosity(at 140° C.) of 20 to 5000 mPa·s.

The oxidized polyolefinic waxes especially have a melt viscosity (at140° C.) of 30 to 2000 mPa·s.

The oxidized polyolefinic waxes preferably have a density of 0.89 to1.00 g/cm³.

The oxidized polyolefinic waxes more preferably have a density (at 20°C.) of 0.91 to 0.98 g/cm³.

The oxidized polyolefinic waxes preferably have acid numbers between 14and 30 mg KOH/g.

The oxidized polyolefinic waxes more preferably have acid numbersbetween 16 and 25 mg KOH/g.

The oxidized polyolefinic waxes are preferably used in the form ofaqueous dispersions.

In summary, the oxidized polyolefinic waxes have drop points of 85 to125° C. and preferably of 90 to 120° C., melt viscosities measured at140° C. of 10 to 10 000 mPa·s, preferably of 20 to 5000 mPa·s andespecially of 30 to 2000 mPa·s, densities (at 20° C.) of 0.89 to 1.00g/cm³ and preferably of 0.91 to 0.98 g/cm³ and acid numbers between 14and 30 mg KOH/g and preferably between 16 and 25 mg KOH/g.

Useful starting materials for the oxidized waxes are homopolymers ofethylene or copolymers of ethylene with one or more 1-olefins. The1-olefins used are linear or branched olefins having 3-18 carbon atomsand preferably 3-6 carbon atoms. Examples thereof are propene, 1-butene,1-hexene, 1-octene or 1-octadecene, also styrene. Preference is given tocopolymers of ethylene with propene or 1-butene. The copolymers are70-99.9% and preferably 80-99% by weight ethylene.

Polyolefinic waxes which are particularly useful have a drop pointbetween 90 and 130° C. and preferably between 100 and 127° C., a meltviscosity at 140° C. between 10 and 10 000 mPa·s and preferably between20 and 5000 mPa·s and a density at 20° C. between 0.89 and 0.98 cm³/gand preferably between 0.90 and 0.97 cm³/g.

Metallocene catalysts for producing the polyolefinic waxes are chiral ornonchiral transition metal compounds of the formula M¹L_(x). Thetransition metal compound M¹L_(x) includes at least one central metalatom M¹ to which at least one π-ligand, for example a cyclopentadienylligand, is attached. In addition, substituents such as for example halo,alkyl, alkoxy or aryl groups can be attached to the central metal atomM¹. M¹ is preferably an element of the III^(rd), IV^(th), V^(th) orVI^(th) main group of the Periodic Table of the Elements, such astitanium, zirconium or hafnium. Cyclopentadienyl ligand refers tounsubstituted cyclopentadienyl radicals and substituted cyclopentadienylradicals such as methylcyclopentadienyl, indenyl, 2-methylindenyl,2-methyl-4-phenylindenyl, tetrahydroindenyl or octahydrofluorenylradicals. The π-ligands can be bridged or unbridged, in which casesingle bridging and multiple bridging—including via ring systems—arepossible. Metallocene also comprehends compounds having more than onemetallocene fragment, so-called polynuclear metallocenes. These cancomprise any desired substitution patterns and bridging variants. Theindividual metallocene fragments of such polynuclear metallocenes can besimilar to or dissimilar from each other. Examples of such polynuclearmetallocenes are described for example in EP 0 632 063 A2.

Examples of general structural formulae of metallocenes and also oftheir use for producing olefin homo- and copolymer waxes are indicatedinter alia in EP 0 571 882 A2.

Oxidation of thus produced waxes in the melt by means of oxygen oroxygen-including gas mixtures by known processes, for instance accordingto EP 0 896 591 A2 or according to EP 0 890 583 A2, provides polar waxyoxidates.

Textile finishing as per the present invention preferably utilizesoxidates of ethylene homopolymer waxes having acid numbers between 14and 30 mg KOH/g, drop points between 90 and 120° C. and melt viscosities(measured at 140° C.) between 20 and 5000 mPa·s.

To be used for textile finishing, the oxidized polyolefinic waxes arepressure emulsified in water in a known manner using nonionic, anionicor cationic emulsifiers.

EXAMPLES

The melt viscosities of the waxes described hereinbelow were determinedin accordance with DGF-M-III 8 (57) using a rotary viscometer, the droppoints in accordance with DGF-M-III 3 (75), the needle penetrationnumbers in accordance with DGF-M-III 9b (95), the acid numbers inaccordance with DGF-M-IV 2 (57) (the DGF standards are standards of theGerman Society of Fat Science), the densities in accordance with DIN53479.

The inventive examples utilized two waxy oxidates (W1/1 and W1/2) whichwere obtained by air oxidation of the metallocene-catalyticallysynthesized polyethylene waxes E1/1 and E1/2. The latter were producedby homopolymerization of ethylene in accordance with Example 2 of EP 0571 882 A2 using bis(indenyl)zirconium dichloride as a catalyst andmethylalumoxane as a cocatalyst, and had the following properties: TABLE1 E1/1 E1/2 Melt viscosity/140° C./mPa · s 190 630 Drop point/° C. 124125 Density/g/cm³ 0.973 0.970 Needle penetration number/0.1 mm <1 <1

The conversion to the oxidates W1/1 and W1/2 (table 2) was carried outwith air in the melt according to Example 1 of EP 0 890 583 A2.

The comparative examples utilized the oxidates W2-W4 from raw materialsproduced without metallocene catalysts. TABLE 2 W1/1 W1/2 W 3 OxidateOxidate W 2 Licowax from from Oxidate PED 821 metallocene metallocenefrom (from W 4 PE wax PE wax Ziegler Clariant A-C 330 E1/1 E1/2 PE waxGmbH, (from Honeywell) Viscosity/ 140 350 200 180 3460 140° C. mPa · sDrop point/° C. 115 116 114 106 130 Needle 2 2 1-2 4 1 penetration in{fraction (1/10)} mm Acid number 18 19 18 16 28 mg KOH/g Density at 0.970.97 0.98 0.95 0.99 20° C. g/cm³

The oxidates W1/1, W1/2 and W2-W4 were used to prepare aqueousdispersions by employing the following emulsifiers:

Emulsifier 1: Synperonic 13/12 (ICI): tridecanol, ethoxylated with 12mol of ethylene oxide.

Emulsifier 2: Genapol OX-100 (Clariant): polyglycol ether based on asynthetic C₁₂-C₁₅ oxo alcohol ethoxylated with 10 mol of ethylene oxide.

Table 3 gives the recipe constituents used to prepare the waxdispersions D1/1-D4 in parts by weight. The emulsifier was dissolved inhot deionized water at about 50° C. and introduced into an autoclavetogether with wax, potassium hydroxide, sodium pyrosulfite and water.This was followed by heating to 115° C. over 20 min, stirring at 115° C.for 20 min and then cooling down to room temperature over 35 min. Thestirrer speed was 200 revolutions per min. TABLE 3 D1/1 D1/2 D 2 D 3 D 4W1/1 27 — — — — W1/2 — 27 — — W2 — — 27 — — W3 — — — 27 — W4 — — — — 27Emulsifier 1 7 7 7 7 7 KOH (86%) 0.5 0.5 0.5 0.5 0.5 Na pyrosulfite 0.30.3 0.3 0.3 0.3 Deionized water 65.2 65.2 65.2 65.2 65.2 Appearance offine fine dispersion fine wax dispersion transparent transparent issolid transparent has not melted dispersion, dispersion, dispersion,liquid LT liquid LT liquid LT 70% 73% 68%

Each polyethylene wax dispersion was rated for quality on the basis ofits light transmission (LT) as measured using an LT 12/transparencymeter from Dr. Lange for a 2 mm cuvette.

The polyethylene wax dispersion used for textile-engineeringapplications should have a light transmission of >50%. This requirementwas only met by the polyethylene wax oxidates W1/1 and W1/2 frommetallocene wax and also by the relatively soft polyethylene wax oxidateW3. The waxes which were not emulsifiable under formulations D2 and D4were emulsified by recipes modified compared with the above procedure(table 4). The polyethylene wax dispersions thus produced showed therequired transparency of >50%. TABLE 4 D5 D6 W2 27.0 — W4 — 27.0Emulsifier 1 7.0 — Emulsifier 2 — 8.0 KOH (86%) 0.5 0.5 Sodiumpyrosulfite 0.3 0.2 Deionized water 65.2 64.3 Emulsifying 135° C. 155°C. temperature Appearance of fine transparent fine transparentdispersion dispersion dispersion liquid slightly viscous Lighttransmission >50% >50%

Textile aftertreating liquors N1/1-N4 were produced by, in each case,stirring 20 g of the polyethylene wax dispersions D1/1, D1/2, D3, D5 andD6 respectively in deionized water together with the synthetic resinproduct Arkofix NDF konz. (modified N-methyloldihydroxyethyleneurea,commercial product of Clariant GmbH) for a wash and wear finish and the3282 catalyst needed to crosslink the synthetic resin finish (catalystbased on metal salt, commercial product of Clariant GmbH) and also with0.5 g of acetic acid and made up to 1 I.

The thus produced aftertreating liquors N1/1-N4 were padded at roomtemperature onto bleached cotton knit at a wet pickup of 70% using alaboratory pad-mangle, subsequently dried at 100° C. for 2 min and curedat 150° C. for 3 min.

The cotton knit aftertreated by this application method with the 5polyethylene wax dispersions D1/1, D1/2, D3, D5 and D6 exhibited thefollowing textile-engineering properties (table 5): TABLE 5 D3 D5 D6 Waxdispersions D1/1 D1/2 (comp) (comp) (comp) Aftertreating liquor N1/1N1/2 N2 N3 N4 Soft hand very very good good very good good good Soilrelease very very good bad very good good good Sewing properties: Needlegauge NM 100 5-10 5-10 5-10 15-25 5-10 Needle gauge NM 90 ca. 2 ca. 2ca. 2  7-12 ca. 2 Needle gauge NM 80 0 0 0 ca. 2 0

The values reported under “sewing properties” indicate the number ofsewing defects per 50 cm of cotton knit. The testing was carried outusing 3 different needle gauges at a sewing speed of 3000stitches/minute.

1. A textile finishing agent comprising an oxidized polyolefinic waxproduced using at least one metallocene catalyst.
 2. The textilefinishing agent according to claim 1, wherein the polyolefinic wax is anethylene homo- or copolymer wax including 0% to 30% by weight of anolefin comonomer having a chain length of 3 to 18 carbon atoms.
 3. Thetextile finishing agent according to claim 2, wherein the olefincomonomer is selected from the group consisting of propene, 1-butene,1-hexene, 1-octene, 1-octadecene and styrene.
 4. The textile finishingagent according to claim 1, wherein the oxidized polyolefinic wax has adrop point of 85 to 125° C.
 5. The textile finishing agent according toclaim 1, wherein the oxidized polyolefinic wax has a drop point of 90 to120° C.
 6. The textile finishing agent according to claim 1, wherein theoxidized polyolefinic wax has a melt viscosity at 140° C. of 10 to 10000 mPa·s.
 7. The textile finishing agent according to claim 1, whereinthe oxidized polyolefinic wax has a melt viscosity at 140° C. of 20 to5000 mPa·s.
 8. The textile finishing agent according to claim 1, whereinthe oxidized polyolefinic wax has a melt viscosity at 140° C. of 30 to2000 mPa·s.
 9. The textile finishing agent according claim 1, whereinthe oxidized polyolefinic wax has a density at 20° C. of 0.89 to 1.00g/cm³.
 10. The textile finishing agent according to claim 1, wherein theoxidized polyolefinic wax has a density at 20° C. of 0.91 to 0.98 g/cm³.11. The textile finishing agent according to claim 1, wherein theoxidized polyolefinic wax has an acid number between 14 and 30 mg KOH/g.12. The textile finishing agent according to claim 1, wheein theoxidized polyolefinic wax has an acid number between 16 and 25 mg KOH/g.13. The textile finishing agent according to claim 1, wherein theoxidized polyolefinic wax is used in the form of an aqueous dispersion.14. A process for finishing a textile comprising the step of applying atextile finishing agent to the textile, wherein the textile finishingagent includes an oxidized polyolefinic wax produced using at least onemetallocene catalyst.
 15. A finished textile made in accordance with theprocess of claim 14.